/*
 * @Description: 1-100的累加
 * @Author: zzj
 * @Date: 2021-09-02 11:23:31
 * @LastEditors: zzj
 * @LastEditTime: 2021-09-02 11:34:44
 */

//累加
const readline = require("readline-sync");
var n = readline.question("请输入一个数字：")
var sum = 0;
for(var i = 1; i<=n;i++){
    sum += i;
}
console.log(n+"的累加结果为"+sum);